Development and performance of anode material based on A-site deficient Sr2-xFe1.4Ni0.1Mo0.5O6-δ perovskites for solid oxide fuel cells

Engineering of A-site deficiency in perovskites can be critical for designing new materials with required functional properties. In this article, A-site deficient Sr2-xFe1.4Ni0.1Mo0.5O6-δ (x = 0-0.1, Sr2-xFNM) perovskites have been synthesized and characterized as anode materials for solid oxide fuel cells. X-ray photoelectron spectroscopy data indicate that Sr deficiency changes valence states of B-site cations. The introduction of A-site deficiency has shown to improve the chemical stability of the as-prepared materials under reducing conditions. With increasing of Sr deficiency, the conductivity in 5% H2/Ar increases markedly, reaching a peak value of 26.6 S cm−1 at x = 0.05. While further increasing of x reduces the conductivity by affecting the mobility of electronic charge carriers. The La0.9Sr0.1Ga0.8Mg0.2O3 electrolyte-supported cell with La0.6Sr0.4Fe0.8Co0.2O3 cathode and Sr1.95Fe1.4Ni0.1Mo0.5O6-δ anode demonstrates a maximum power density of 606 mW cm−2 at 800 °C operating in H2. Such designed A-site deficiency perovskite has the potential to be applied as SOFC anode materials.